In automated warehouses or so-called goods distribution centers, respectively, it is common to employ so-called “high-bay warehouses” which are designed as multistory buildings. For the storage and disbursement of loading devices with goods arranged upon them, floor-bound rack operation equipment is conventionally used which is combined with a conveyor system for storage and disbursement. The conveyor system is in most cases adapted to the respective requirements, for example the type of transport goods or the project requirements, so that different measures for conveyance can be taken. For example, stationary conveyors, such as roller conveyors, chain conveyors, deflection devices or rail-bound distribution trolleys, or else movable conveyors, such as driverless transport systems (DTS), electric ground conveyors (EGC), or electric overhead conveyors (EOC), can constitute the conveyor system.
There are different designs of “driverless” transport systems. Driverless transport systems are often employed which combine a trolley with a stationary conveyor which can accept goods to be conveyed on a loading device in a horizontal movement. Furthermore, counterweight trolleys are employed which are combined with a lifting device, such as forks of a stacker, and can thus lift, carry and lower pallets. Moreover, systems are employed which can drive under goods on a loading device to be conveyed and lift the latter from a device, transport them by carrying them and deposit them on devices. Lifting can be accomplished, by way of example, by a rotating spindle or by lifting columns, eccenters, etc.
In a conventional warehouse, the transport of the goods is accomplished, for example, from the disbursement conveyor system to shipping via a pallet handling system, or alternatively via an electric overhead conveyor or electric ground conveyor. In the shipping area, the goods are usually distributed onto gravity roller conveyors by means of cross transfer trolleys to make them ready for shipping. In plants with high performance requirements for sequencing the goods in shipping in the working range of the cross transfer trolleys, driven conveyor elements can be additionally attached on which the goods can be temporarily buffered and where the goods are subsequently withdrawn in the correct sequence and conveyed onto the gravity roller conveyors for shipping.
All conventional stationary conveyor solutions have considerable disadvantages in view of the flexibility of their utilization and are complicated to commission. The use of conventional conveyor technology requires repeated pallet transfers from one conveyor element to the next conveyor element. Each of these transfers represents a possible source of interference. Moreover, in case of maintenance or repairs, the conveying capacity is affected.
The movable conveyors offer more flexibility in view of expandability, change of travel ways, and trolley distribution, in particular the not rail-bound driverless transport systems. In many logistic solutions, the movable conveyors are combined with conventional conveyors, in particular when automatic storage systems are involved, and thus, the possible advantages of the movable conveyors are reduced.
It is therefore an object to provide a system with driverless transport systems for transporting goods arranged on loading devices, in particular in the spatial environment of a high-bay warehouse, which permits transport of the goods between the high-bay warehouse and further areas, the system including high flexibility in view of trolley expansion, changes of travel ways, and trolley distribution, and requiring only low complexity due to passive transfer devices, no cabling and electric and control-related commissioning, which is required in conventional conveyors or rail-bound systems.